If nC12 = nC5, find the value of n. – InterviewSolution

InterviewSolution

1.

If nC12 = nC5, find the value of n.

Answer»

As we know that if ⁿC_p = ⁿC_q, now one of the following conditions need to be satisfied:

(i) p = q

(ii) n = p + q

Therefore from the question ⁿC₁₂ = ⁿC₅, we can say that

12 ≠ 5

Therefore, the condition (ii) must be satisfied,

n = 12 + 5

n = 17

∴ The value of n is 17.

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